Electrically driven erasing machine



Jan. 10, 1939.

B. F. HALL 2,143,124

ELECTRICALLY DRIVEN ERASING MACHINE Filed June 9; 1957 III;

HIIIIIIH Patented Jan. 10, 1939 I UNITED STATES PATENT OFFICEELECTRICALLY DRIVEN ERASING MACHINE Benjamin Fairfax Hall, London,England Application June 9, 1937, Serial No. 147,392 In Great BritainJuly 15, 1936 3 Claims. (Cl. 120-36) This invention relates to erasingmachines of machine around the windings of the motor D the kind in whichthe erasing material is rapidly and out through the annular space aaround rotated by means of an electric motor, and has and along thechuck F, thereby preventing the for its object to provide means wherebya curparticles from the eraser f and the particles 5 rent of air iscaused to pass through the machine erased from accumulating,consequently permit- 5 when in use so that the particles of the erasingting the operator a clear view of the matter to medium and the erasedparticles are blown away, be erased. Further, as the air passes over thethus giving the operator a clear view of the matwindings of the motor Dit prevents the temter to be erased, and at the same timepreventperature of such windings rising above a satising the temperatureof the windings of the motor factory limit. l0

rising above satisfactory limits. A handle H, preferably formed on eachha According to this invention, in the interior of of the body or casingA where they join, is prothe easing of body of the machine which isvided for holding the machine when being opformed in two parts, I mounta fan co-axially on erated,

that end of the motor spindle opposite to the If found necessary, I mayprovide holes in 15 end which carries the erasing chuck. This end theend of the casing A surrounding the chuck of the motor spindle may p ejet t an F to assist the passage of air issuing through Opening in the endof e body or cas su the annular space a around said chuck.

Opening being sufileiently large to ve h What I claim as my inventionand desire to nular space around the spindle to permit air to ecur by Ltt t t i 20 be Sucked in therethleilgh y the The D 1. An'electricallydriven erasing machine having in the DDOS d of he as o y ing an eraserchuck, air pump means located at th o W ch t e h c Carrying the a e therear of the machine, and means for directing p oj ts s alS0 sufli ientlvlarge to permit the a current of air therefrom through the machinecurrent Of air drawn into the machine to be .and axially along andaround the periphery of 25 blown out through this opening. the eraserchuck.

The invention is illustrated o the p y- 2. An electrically drivenerasing machine having drawing. ing a casing and a motor, a fan mountedco- 1 s a Side View Of an electrically driven axially on the rear end ofthe motor spindle in erasing machine constructed according to this thint i f th asing, an opening in the 30 invention. rear of said casingthrough which said end of 2 is a Similar View With the One half of thespindle projects, said opening being sufi'lclentthe easing bedy removedShowing the interly large to leave an annular space around said Dalmechanism P y in section. projecting end of the spindle to permit air toFi 3 s ap Sectional rear end View Of be sucked therethrough by said fan,the other 35 A represents the y easing of the end of the motor spindleprojecting through the chine which is formed in tWO parts, B the fan,casing and carrying an eraser chuck, and an D the motor and E t SpindleOn which Said fail annular space around the opening in the casing 13 ismounted. through which the chuck carrying spindle end 40 According tothis invention I mount the fan project sufnciently large t permit tcurrent 40 B co-axlaiiy on the end of the Spindle E, of air drawn intothe machine to be blown out the eraser chuck F being fixed on theopposite through said Owning end 62 of said Spindle' The 81 of thespindle 3. An erasing machine comprising a casing, an projects throughan opening the casing electrical motor therein and having a spindle 5such opening being sufhciently'large to leave an projecting through thecasing ends, an eraser l 232 g? 3: g gzg i g ig g gfi i g gfi carryingchuck on one end of the spindle exterfan B The opening a2 in theOpposite end of nally of the casing, and a fan fixed on said spinthecasing A through which the chuck F, carrydle at the oppflslte p of thecasmg' Sald fan ing the eraser 1, projects is also sufllciently h the asg being apertured for entry of 50 large t pennit t current of air drawnthrough air blown by the fan through the casing over said the opening ainto the machine to be blown meter, and said casing at the chuck endbeing out through said opening a at and axially along axially aperturedin a manner to direct air from the periphery of the chuck and eraser.the fan axially along and over the periphery of When the machine is inoperation as air is said chuck.

sucked in by the fan B it passes through the BENJAMIN FAIRFAX HALL.

